This evaluation is recommended for patients presenting with lifelong erythrocytosis, usually with a positive family history of similar symptoms. Polycythemia vera should be excluded prior to testing as it is much more common than hereditary erythrocytosis and can be present even in young patients. A JAK2 V617F or JAK2 exon 12 mutation should not be present. Additionally, p50 testing should be performed and a normal result confirmed before ordering this test. Serum Epo levels are typically normal (inappropriately so for the level of hemoglobin). For a complete evaluation including p50 testing, hemoglobin electrophoresis testing, and hereditary erythrocytosis mutation analysis in an algorithmic fashion, order the erythrocytosis evaluation panel (REVP / Erythrocytosis Evaluation).